On Sunday 19th August Hydrosave were mobilised to assist in the repair of a seized butterfly fly valve that was hindering the repair of a trunk mains burst. The team were on site within two hours and procedure to repair the gearbox on this small 10” valve. Drive to the valve had been lost due to damage to the internal components of the gearbox and an attempt to operate the valve by the R&M contractor was unsuccessful due to the valve also being seized. The Hydrosave team removed the gearbox and damaged parts, repaired on site, lubricated, reassembled, adjusted the indicator plate and the released the valve within an hour.
This is a very common occurrence with all butterfly valves, especially the smaller ones as the gearboxes aren’t capable of handling the forces sometimes needed to operate a stiff valve. This is where comprehensive valve assessment comes into its own in identifying problematic valves for planned maintenance activities or contingency planning for future operations.